The objective of the proposed research is to evaluate adoptive immunotherapy in AKR mice bearing spontaneous leukemia-lymphoma. Bacterial decontamination and axenic isolation will be used to prevent the major complication of adoptive immunotherapy, secondary disease. In the planned experiments, we will develop and test systems for bacterial decontamination and axenic isolation of AKR mice after appearance of clinically evident spontaneous leukemia-lymphoma. In order to evaluate possible beneficial effects of decontamination and isolation procedures, conventional and decontaminated leukemic AKR mice will be treated with adoptive immunotherapy in combination with chemoradiotherapy and observed for survival. We will also evaluate reconventionalization of decontaminated, treated AKR mice by a step-wise reassociation with non-pathogenic bacteria at various intervals following adoptive immunotherapy.